JPH07206936A - Copolymer of ethylene oxide with at least one substituted oxirane having crosslinking function, its production, and its use for production of ionically conductive substance - Google Patents

Abstract

PURPOSE: To obtain a copolymer of ethylene oxide with at least one oxirane having a crosslinking function, a process for producing the same, and its use for the production of a solid electrolyte having good mechanical properties, good cationic conductivity, and good chemical compatibility in relation to the electrode of a generator acting on an alkali metal such as lithium or sodium.

CONSTITUTION: There is provided a copolymer having a chain comprising ethylene oxide, i.e., O-CH₂-CHR units (wherein R is a substituent having reactivity; this substituent has the function of crosslinking by a free radical process, provided that R in one unit may be different from R in another unit), and optionally, O-CH₂-CHR' units (wherein R' is a substituent having the function of crosslinking by a free radical process and containing a nonreactive function, provided that R' in one unit may be different from R' in another unit), or the like, and having an excellent polymolecularity index I=Mp/Mn and a statistical distribution of different monomer units.

COPYRIGHT: (C)1995,JPO

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a copolymer of ethylene oxide and at least one substituted oxirane having a crosslinkable function, a method for producing the same, and a generator acting with an alkali metal such as lithium or sodium. The use of the copolymers for producing solid electrolytes having good mechanical properties, good cation conductivity and good chemical compatibility for the electrodes.

[0002]

It is known to use solvent-based polymers for producing ion-conducting materials. Polymers of ethylene oxide or dioxolane are polymers of solvent-type cations, in particular alkali cations, such as Li ⁺ ions, which are present in polymer electrolyte lithium battery type rechargeable electrochemical generators. However, these polymers are semi-crystalline and the varying degree of crystallinity has a function of the molecular weight of the polymer. This semi-crystalline character of the polymer exists in the polymer as important to reducing the conductivity of the material.

Secondly, by introducing irregularities into the polymer chains at irregular intervals as much as possible, the semi-crystalline material is obtained without affecting the solvation properties and electrochemical stability of the polymer. It has been found possible to reduce the crystallinity of the polymer. However, semi-crystalline polymers such as polyoxyethylene (PO
The introduction of macromolecules such as E), in other words the replacement of semi-crystalline polymers by copolymers or polycondensates, is often carried out, for example by reducing the molecular weight and mechanical properties at elevated temperatures. Have been confirmed.

[0004] By introducing this approach into polymers, the above-mentioned disadvantages have been overcome and the constitutional units allow the formation of three-dimensional networks by means of crosslinkable copolymers. Due to the constraints imposed by the electrochemical stability requirements, particularly preferred units that allow crosslinkability are selected among those containing unsaturated carbon / carbons such as allyl or vinyl bonds. By introducing such a unit into the copolymer, various groups such as ionic groups can be further immobilized on the polymer chain.

From ethylene oxide and oxiranes having unsaturated substituents by coordination polymerization using initiators based on organometallic derivatives of non-alkali and non-alkaline earth metals such as alkylaluminum or alkylzinc. It is known to produce copolymers. This polymer is not unstable in the presence of small amounts of impurities.
However, the reactivity of different comonomers depends on these steric hindrances. Thus, when a copolymer of ethylene oxide and an oxirane having a saturated group (eg, propylene oxide) or an oxirane having an unsaturated group (eg, allyl glycidyl ether) is produced, the polymerization yield of ethylene oxide is The rate is close to 100%, but 10
Polymerization yields of substituted oxiranes in copolymers with high molecular weight above 00 are only 60%. In addition, ethylene oxide is preferably consumed early in the polymerization. The copolymer formed in the early stage of the polymerization due to the different reactivity of the monomer contains a large number of ethylene oxide, and has a higher molecular weight than the copolymer formed in the middle or end of the polymerization reaction. The copolymer thus formed by coordination polymerization is crystalline and has a long sequence of poly (oxyethylene) which exhibits high molecular weight heterogeneity.

It is known to polymerize saturated oxiranes such as ethylene oxide or propylene oxide by ionic polymerization. If the polymerization is carried out in aqueous solution or in a protic solution such as ethylene glycol with a sodium or potassium hydroxide type initiator, some chain transfer reactions occur in this solution and the molecular weight obtained is Markedly reduced. When the ionic polymerization of oxiranes is carried out in the presence of a potassium alcoholate or cesium alcoholate-type initiator in an aprotic solvent that solvates cations, or in the presence of a complex reagent such as crown-ether, Ethylene oxide undergoes living polymerization, in other words, the number average degree of polymerization (DPn) increases the conversion rate, the distribution of molecular weight becomes smaller, the polymolecularity index I = Mp / Mn becomes close to 1, and the chain Transfer and termination reactions will not occur. Ionic polymerization carried out under these conditions makes it possible to obtain large amounts when the polymer is ethylene oxide.

However, when used together with a substituted oxirane type monomer, only an oligomer has been obtained to date. For example, the polymerization of styrene oxide initiated with potassium tert-butanolate is 100
Giving poly (oxystyrene) with an amount of 0 g, and the growth of poly (oxypropylene) chains is blocked by the chain transfer reaction on the monomer [DM Simons and
JJ Verbane, J. Polym. Sc. 1960, 44 , 303].

When the monomer is phenylglycidyl ether, the growth of the polymer is rapidly stopped by the chain transfer reaction with the monomer [CC Price, Y.
Atarachi, R. Yamamoto, J. Poly. Sci. PartAl, 1969,
7 569]. Despite the advantages of anionically polymerized with a nearly quantitative conversion rate, the prior art shows strong properties of polymerisation only for ethylene oxide.

[0009]

The object of the present invention is to provide a copolymer of ethylene oxide and at least one substituted oxirane having a crosslinking reactivity function by a free radical process. The copolymer has improved mechanical properties compared to materials obtained from known copolymers of the poly (oxyalkylene) type, without reducing ionic conductivity due to multiple cross-linking points that reduce the glass transition temperature Tg. It is an object of the present invention to provide an ion-conducting material which has excellent chemical compatibility as an electrode of a generator when the material is used as an electrolyte. With the goal.

[0010]

DISCLOSURE OF THE INVENTION An object of the present invention is to provide an ethylene oxide unit, an —O—CH ₂ —CHR— unit (wherein R is a substituent having a reactive function capable of crosslinking by a free radical process, R may differ from one unit to another), and optionally a —O—CH ₂ —CHR ′ unit, where R ′ contains a non-reactive function that is crosslinkable by a free radical process. R'is a substituent, and R'may be different from one unit to another unit) and the like, and the polymer has an excellent heavy molecular weight ratio index I = Mp / Mn. And a copolymer having a statistical distribution of different monomer units.

Among the copolymers of the present invention, these copolymers have an average molecular weight of 20,000 or more in Mn number, and particularly Mn number of 100,000 or more is particularly interesting.

An excellent index of heavy molecular weight means an index of 2.2 or less. Generally, the copolymers of the present invention will range from 1.5 to
It has a heavy molecular weight index in the range of 2.2.

The different units are randomly arranged in the chain of the copolymer of the present invention. However, sequences composed of chains of identical monomer units are more regular than known methods, in other words copolymers obtained by coordination polymerization. As such, it is relatively easy to predict sequence lengths that depend only on the relative proportions of the monomers.

The statistical distribution of the monomer units is an important index when the resulting copolymer undergoes grafting to fix an ionic group based on the reactive function of the substituent R of the oxirane unit. Statistical distribution of ionic groups is important to prevent the generation of passage properties for ions when the copolymer is used as an ion conducting material.

The --O--CH ₂ --CHR of the copolymer of the present invention
In the unit, the reactive function that is crosslinkable by the free radical process and that is present in the R group favors the unsaturated carbon / carbon bond. The R group in this case has the formula CH ₂ ═C
H- (CH ₂ ) q- (O-CH ₂ ) p (wherein 1 ≦ q ≦
6 and p = 0 or 1), or the formula CH ₃ — (CH
_{2) y -CH = CH- (CH} 2) x- (OCH 2) p
It can be selected from the specific radicals having (where 0 ≦ x + y ≦ 5 and p = 0 or 1). In the same polymer chain, the unsaturated groups R do not have to be the same.

The copolymer of the present invention --O--CH ₂ --CH
In the R'-unit, the non-reactive substituent R'which is crosslinkable by a free radical process is an alkyl group, preferably an alkyl group having 1 to 16 carbon atoms, more preferably 1 to 8 carbon atoms. It can be selected from among alkyl groups having atoms.

Further, the substituent R'is a group-(CH ₂ ) n--O.
_{- ((CH 2) m-} O) p-CH 3 ( wherein, 0 ≦ n ≦
4, 1 ≦ m ≦ 4, and 0 ≦ p ≦ 20, preferably n =
1, m = 2 and 0 ≦ p ≦ 8). Further, the substituent R ′ can be selected from an alkyl (perfluoroalkyl sulfonate) ether group. As a specific example, the formula —CH ₂ —O
_{- (CF 2) q-CF} (Cr F2r + 1) in -SO ₃ M (wherein, M represents a cation of alkali metal, 0 ≦ q ≦ 4,
A group having q = 0 or 1 and 0 ≦ r ≦ 4, more preferably 0 ≦ r ≦ 3 can be mentioned. Preferred groups of these categories, -CH ₂ -O
_{-CF 2 -CF 2 -SO 3 M,} -CH 2 -O-CF 2 -
_{CF (CF 3) -SO 3 M} , and -CH ₂ -O-CF ₂
Mention may be made of the -SO ₃ M.

The substituent R'has a negative charge of bis (trifluoromethylsulfonyl) methylide-C (SO ₂
CF ₃ ) ₂ M ″ can be selected from groups containing an electrophoretic function generated by a carbanion. Among these, —CH ₂ —C (SO ₂ —CF ₃ ) ₂ M ″ and —
_{(CH 2) s-SO 2} -C (SO 2 -CF 3) 2 M "
(Wherein 1 ≦ s ≦ 16, preferably 0 ≦ s ≦ 8, M ″ is a metal cation, particularly a monovalent cation such as an alkali metal cation). _{2
-C (SO 2 -CF 3) 2} M " , and - (CH ₂₎ s-S
_{O 2 -C (SO 2 -CF 3} ) 2 M " groups are particularly preferred.
In the same polymer chain, all the substituents R'may not be the same.

The copolymers of the invention having a high Mn number average molecular weight, in particular at least 20,000, preferably at least 100,000, are of two interest.
On the one hand, these copolymers, in the non-crosslinkable state, have unique mechanical properties which are superior to conventional homopolymers of the same type. These copolymers can be manufactured and handled in thin film form prior to crosslinking. Furthermore,
These copolymers can be used as elastic adhesives or adhesives when assembling generator parts. If crosslinkability is required, a lower proportion of crosslinkable function can be used.

On the other hand, the high molecular weight makes it possible to use a larger amount of the polymerization initiator and limits the valence of the termination reaction function of alcoholates and hydroxyls. In the copolymers of the present invention having a molecular weight of at least 20,000, reactive chemical groups (termination function, polymerization initiator, alkali metal sensitive crosslinkable function, light weight diffusible in the electrode). The double limitation of the concentration and mobility of the polymer) is important. This group of reactive chemistries is of great interest when the copolymers according to the invention are used as ion-conducting materials in generators operating with, for example, alkali metals. In this case, the ionic conduction of the ion-conducting material containing the copolymer is not substantially reduced by the crosslinking, because the low rate of crosslinking has little effect on the glass transition temperature Tg. In addition, the electrochemical compatibility between the ion-conducting material used as the electrolyte and the electrodes of the generator is clearly high.

As a notable embodiment, the copolymers according to the present invention have at least 70 mol% of oxylene units, about 2-3, having the function of being crosslinkable by a free radical process.
0 mol% of the saturation unit -O-CH ₂ -CHR ', and about 0.05 to 10 mol% of -O-CH ₂ -CHR- units.

The copolymer of the present invention is obtained by an anionic copolymerization reaction. Moreover, the objective of this invention is providing the manufacturing method of the said copolymer.

The method for producing a copolymer according to the present invention comprises the steps of adding ethylene oxide and one or more substituted oxiranes (provided that at least one substituent R has a function capable of being crosslinked by a free radical process). Reacting in the presence of an ionic polymerization initiator in an organic solvent, the monomer and solvent used have a certain humidity and impurities of 100 ppm or less,
It is characterized in that the reactor used for the polymerization reaction is free from humidity and traces of impurities.

As described below, an oxirane having a substituent containing a function capable of being crosslinked by a free radical process can be represented by the term unsaturated oxirane. An oxirane having a substituent containing a non-crosslinking function can be represented by the term saturated oxirane.

The polymerization initiator is selected from alkali metals in which the polymerization initiator is used in the form of alcoholate or in the metal form of a complex such as crown-ether. The alkali metal is preferably selected from cesium and potassium. Potassium alcoholate is particularly preferred.

When the initiator is an alkali metal or an alkali metal alcoholate, the neutral solvent used in the polymerization is selected from polar solvents. Specific examples of polar solvents include THF, dimethoxyethane and dimethylsulfoxide. However, in view of the fact that the ethylene oxide and oxirane type monomers are polar, polar solvents such as THF are used at 1%
It is possible to use non-polar solvents, such as toluene, which contain minor amounts.

When the initiator is used with a complexing agent such as crown ether, the neutral solvent may be a polar solvent or a non-polar solvent such as toluene.

The production method of the present invention is carried out using at least one unsaturated oxirane. From suitable unsaturated oxiranes, the following formula:

[Chemical 3] And oxirane having R, where R is as defined above. Allyl glycyl ether and epoxy hexene are particularly preferred unsaturated oxiranes.

The function of the units derived from unsaturated oxiranes makes it possible to crosslink the copolymer after it has been obtained or to graft it onto substituents, for example for fixing ionic groups in the polymer chain. Allow the reaction.

Small amounts of impurities in the monomers and solvents used to polymerize can be obtained by treating the monomers and solvents with molecular sieves or, in the case of ethylene oxide, by distillation.

Pretreatment of the reactor to remove impurities can be carried out, for example, by washing the reactor with a solution containing the initiator and removing the initiator solution before introducing the reagents.

When carrying out the process according to the invention, the reaction mixture contains a very small amount of impurities so that a chain termination reaction can take place. Therefore, the yield of the reaction is very high, reaching a value close to 100%. The copolymer thus obtained contains a small amount of residual monomer such that it does not need to be removed, but it has a high boiling point (eg 150 ° C.).
This is an important advantage when using a monomer having a higher).

Further, the production method of the present invention comprises ethylene oxide, at least one unsaturated oxirane and at least one unsaturated oxirane.
It can be used to copolymerize individual saturated oxiranes. By introducing saturated oxiranes into the copolymer, the crystallinity of the copolymer can be reduced or even modified, and the mechanical properties of the copolymer can be modified. The saturated oxirane has the following formula:

[Chemical 4] (In the formula, R ′ is the same as mentioned above) and oxirane corresponding thereto.

When the copolymer of the present invention is to be used for producing an ion conductive material, it can be effectively used to inactivate the termination reaction function of the polymer chain ( However, in this case there are not many because of the high molecular weight).

The stopping function is generally an alcoholate or O.
H functions, which are highly reactive with lithium electrodes and contribute to the decomposition of the polymer electrolyte / lithium electrode interface. Thus, the manufacturing method of the present invention can effectively include the additional step of inactivating the stopping function.

This inactivation can be carried out with 2-bromo-1-cyano-ethane according to the following reaction scheme. PO ⁻ , K ⁺ + BrCH ₂ —CH ₂ —CN ⇒ PO−
CH ₂ —CH ₂ —CN + KBr (however, PO ⁻ and K ⁺ are copolymers that are not inactivated)

Further, inactivation of the termination function can be carried out by using methyl iodide or methyl sulfate. In this case, the copolymer has a methoxy terminating group, and when the inactivating terminating function is potassium alcoholate, potassium iodide or potassium sulphate is formed, respectively.

The properties of the copolymers of the present invention make them particularly useful for making materials with ionic conduction. A high molecular weight, as mentioned above, has a beneficial effect on the mechanical properties on the one hand and on the other hand on the electrochemical properties. Furthermore, the statistical distribution of unsaturated functions makes it possible to obtain homogeneous crosslinks if these functions are used for the crosslinks. When these functions are used to graft ionic groups onto the copolymer, the statistical distribution of the grafted ionic groups makes it possible to prevent the generation of properties that allow ions to pass through. .

To produce the ion-conducting material, it is derived from at least 70 mol% ethylene oxide units, from about 2 to 30 mol% units derived from at least one saturated oxirane and from at least one unsaturated oxirane. Copolymers containing from about 0.05 to 10 mol% units can be used.

If this material is used without solvent or with small amounts of solvent (less than 10% by weight),
The content in the unit derived from unsaturated oxirane is preferably in the range of 0.05 to 1 mol%. If this material is used in the solvent swollen state, the content of units derived from unsaturated oxiranes can reach up to 10 mol%.

Units derived from unsaturated oxiranes are
If used to graft ionic groups onto the copolymer, their content is preferably in the range 3 to 5 mol%.

According to a particular embodiment, the ion-conducting material according to the invention essentially comprises one ionic compound capable of easily dissociating the copolymer according to the invention in solution. The ionic compound introduced into the copolymer or the crosslinked polymer before crosslinking is selected from the ionic compounds usually used for the material of the conductive solid polymer mentioned at the beginning.

[0043] According to an embodiment, ionic compounds These ionic compounds (1 / aA) ⁺ Y ^- wherein, A a ⁺ is a proton, a metal cation, organic cations of ammonium, amidinium or guanidinium type, a is Indicates the valence of a cation, Y ⁻ is an anion from which electronic charge is removed,
For example, Br ⁻ , ClO ₄ ⁻ , AsF ₆ ⁻ , RfS
_{^{O 3 -, (RfSO 2)}} 2 N -, (RfSO 2)
_{^{3 C -, C 6 H (}} 6-X), (COCCF 3 SO 2) 2
C ^-) x or _{C 6 H (6-x)} (SO 2 (CF 3 S
O _{²⁾ 2} C- -) indicates a perfluoroalkyl group or perfluoroalkyl allyl group (1 ≦ x ≦ 4 in the formula is as Rf), and the like.

Lithium is a preferred ionic compound.
Salt, more preferably (CF₃SO₂)₂N^-Li⁺, C
F₃SO₃ ^-Li⁺, Compound C₆H_(6x)-[CO (CF
₃SO₂)₂C^-Li⁺]_x(In the formula, x is in the range of 1 to 4
And preferably x is 1 or 2), compound C
₆H_(6x)-[SO₂(CF₃SO₂)₂C^-Li⁺] _x
(X is in the range of 1 to 4, preferably x is 1 or 2
It is) and the like. These salts are one salt and
Can be used as a mixture with other salts.

In this embodiment, (CF₃SO₂)₂
N^-Li⁺And CF₃SO₃ ^-Li ⁺Or (CF₃SO
₂)₂N^-Li⁺And C₆H_Four-[CO (CF₃S
O₂)₂C^-Li⁺]₂Salt mixed with various ratios
However, preferably 20 to 40% by weight of (C
F₃SO₂)₂N^-Li⁺It is preferable to contain
The ionic compound can be in the form of a film.
By immersing the polymer in the chosen solution in a solvent
It can be incorporated into the copolymer and its solvent is then vaporized.
Can be emitted. Another example is ion
Is the compound a solution containing both the copolymer and the ionic compound?
Film into the copolymer
You can

According to another embodiment, the ion-conducting material according to the invention consists essentially of the copolymer according to the invention and the ionic compound containing unsaturation is --CH ₂ --CHR--.
It is grafted with radicals R by co-crosslinking with O-units. In this case, about 3-5 mol%-
CH ₂ -CHR-O- unit according to the present invention containing the copolymer is preferably used.

Since it is grafted with the radical group R,
WO93 / 1698 from among suitable ionic compounds
Sultone having an ionic group described in 8
Examples of the derivative of CH include CH₂= CH-CH₂-(C
F₂)₂-SO₃M ', CH ₂= CH-CH₂-OC
F (C_yF_{2y + 1}) -CF₂SO₃M'and CH₂= CH
-CF (C_yF_{2y + 1}) -CF₂SO₃M ′ (where 0 ≦
y ≦ 4, preferably 1 ≦ y ≦ 3M ′ is a proton or a metal cation.
Ions, more preferably monovalent metal cations, organic cations
On) can be used. Metal io
Of these, alkali metal cations are particularly preferable.
Among the organic cations, ammonium cation and guanine
Such as a cation and an amidinium cation.
And these organic cations can be quaternized
It Also, [CH₂= C (CH₃) -CO-C (SO₂
-CF₃)₂]^-Li⁺, [CH₂= C (CH₃) -C
(SO₂-CF₃)₂]^-Li⁺, [CH₂= CH-C
H₂-CO-C (SO₂-CF₃)₂]^-Li⁺, [C
H₂= CH-Φ-SO₂-C (SO₂-CF₃)₂]^-
Li⁺, [CH₂= CH-CH₂-SO₂-C (SO₂
-CF₃)₂]^-Li⁺, [CH₂= CH-SO₂-C
(SO₂-CF₃)₂]^-Li⁺, [CH₂= CH-Φ
-CO-C (SO₂-CF₃)₂]^-Li⁺Such as screw
(Trifluoromethylsulfonyl) -methylide salt
Can be mentioned.

As yet another specific example, the ion-conducting material is essentially —CH _{2 in} which the radical group R ′ contains an ionic group.
It can consist of a copolymer according to the invention containing -CHR'-O- units. The ionic group is bis (trifluoromethylsulfonyl) methylide-C (SO ₂ CF ₃ ) ₂
M "group (wherein, M" is a metal cation, preferably an alkali), or _{-CH 2 -O- (CF 2) q} -CF (C r F
_{2r + 1} ) -SO ₃ M type perfluorosulfonyl (in the formula, M represents a monovalent metal).

Next, the --CH ₂ --CHR '-O-- unit is 2
Fulfills individual functions. On the one hand, these units reduce the regularity of solvating the polymer chains and consequently the crystallinity. On the other hand, these units give the copolymer cation monopolar ionic conductivity properties.

The different means mentioned above for introducing ionic species into the copolymers according to the invention for producing ion-conducting materials can also be combined, if desired.

The properties of the final material can be modified by adding various additives to the material of the present invention. As such an additive, ethylene carbonate,
Propylene carbonate, r-butyrolactone, dimethylformamide, N-methyl-pyrrolidone, tetraalkylsulfamide, methyl ethers of polyethylene glycol having a molecular weight in the range of 200 to 2000, and derivatives of polar molecules with low volatility in general. A reagent that imparts plasticity such as can be mixed. The proportion of these additives can be in the range of 1 to 90% with respect to the total amount.

The material having ionic conductivity of the present invention comprises a copolymer and an ionic compound, or a copolymer having an ionic substituent, and in particular, the copolymer is at least 20,0.
When it has a molecular weight of 00, it can be used as a component of a solid polymer electrolyte for separating electrodes and / or a composite electrode.

Consequently, it is an object of the present invention to provide an electrochemical cell in which the electrolyte comprises an ion-conducting material according to the invention and / or at least one of the electrodes is a composite electrode comprising such a material. To provide. In a particular embodiment, the electrolyte is a membrane separating the electrodes, which membrane consists of an ion-conducting material according to the invention, for example a suitable mixture of ethylene carbonate / propylene carbonate (weight ratio about 1/1). It is plasticized by adding different solvents.

The ionic conducting copolymers and materials of the present invention can be recharged or not rechargeable.
It is useful as an electrochemical generator having an alkali metal. This generator comprises a negative electrode and a positive electrode separated by a solid polymer electrolyte containing a copolymer according to the invention. In such a generator, the electrodes can include the ion-conducting material of the present invention which acts as a conductive binder when manufactured as a composite form.

For this particular application, the copolymers of the invention are of particular interest because they contain the few species capable of interfering with electrochemical reactions. In fact, the high average molecular weights obtained substantially reduce the number of reactive ends, and the high conversion limits the residual catalyst content. Moreover, the high average molecular weight that the copolymer can have gives it sufficient inherent mechanical properties when there is no cross-linking between the copolymer and the ion-conducting material present in the copolymer. However, when cross-linking is required, the statistical distribution of cross-linking units makes it possible to obtain very identical cross-links.

The copolymers and ion-conducting materials may also be used in other electrochemical systems such as electrochromic systems, systems for modulated light, and systems for the production of selective membranes or membranes referred to as membrane extraction. Useful for.

The invention is illustrated by the following examples, but it is understood that the invention is not limited to the examples given.

In the following example, the polymerization was carried out on a stainless steel pearl (Parr (registration number)) with a capacity of 2 liters, provided that it was equipped with a stirrer and a bottom valve allowing the reactor to be emptied from the bottom. ) Performed in reactor. All transfer operations were carried out under an inert atmosphere by using very dry argon or nitrogen without oxygen.

In each example, the reactor was washed with the initiator solution before introducing the reagent into the reactor, and the initiator solution was removed and the reactor was dried.

The content of water contained in these is 100 pp
Ethylene oxide was distilled so that it was less than m (this value can be ascertained by the Karl-Fisher method) and dried over a molecular sieve before introducing the solvent and monomers used into the reactor.

[0061]

EXAMPLES Example 1 Water and traces of impurities were removed and 250 ml of toluene,
10 ^-3 mol potassium tert-butanolate and 3 m
83.9 g of ethylene oxide, 10 g of methyl glycidyl ether and 5.1 g of allyl glycidyl ether were introduced into a reactor containing 1 l of THF. The temperature of the reactor rose to 120 ° C and was maintained for 22.5 hours.
A decrease in pressure was observed from 10.3 × 10 ⁵ Pa to 1 × 10 ⁵ Pa. Then, the temperature was lowered to 70 ° C., and 3-tert-butyl-4-hydroxy-5-methyl-phenyl sulfate 1 commercially available from Aldrich Co., Ltd.
00 mg was added. This product is used as a stabilizer and antioxidant for polymers. Next, after washing the reactor with a small amount of toluene and distilling the solvent, 100%
93 g of the copolymer corresponding to the above yield was recovered. DSC analysis of this copolymer showed a melting point Tf of 30 ° C and a glass transition temperature Tg-64 ° C. The number average molecular weight is SEC (ster
It is determined by ic exclusion chromatography, and it is about 105,000.
dex) was 1.7.

Example 2 Water and traces of impurities were removed, 115 ml of toluene,
87.2 g of ethylene oxide, 9.8 g of methyl glycidyl ether and 5 g of allyl glycidyl ether were introduced at room temperature into a reactor containing 2.10 ^-3 mol of potassium tert-butanolate and 6 ml of THF. The reactor temperature rose to 120 ° C and was maintained at that temperature for 22 hours. The pressure was remarkably reduced from 10.3 × 10 ⁻⁵ Pa to 1.4 × 10 ⁻⁵ Pa. Then, 3-tert-butyl-4-hydroxy-5-methyl-phenyl sulfate 1
00 mg was added. After distilling the solvent, the copolymer was recovered with a yield of 85%. A substantial portion of the recovery loss is due to the fact that a small amount of the copolymer remained stuck to the reactor walls. DSC analysis of this copolymer shows melting point Tf30
And a glass transition temperature Tg-61 ° C. The number average molecular weight is determined by SEC (steric exclusion chromatography), and is about 80,000.
The ymolecularity index) was 1.9.

Example 3 To a reactor free of traces of water and impurities, 250 ml of toluene, 10 ^-3 mol potassium t-butanolate and 3 ml THF were added. The temperature of the reactor rose to 110 ° C., after which 90.2 g of ethylene oxide, 8.4 g of methyl glycidyl ether and 1.9 g of allyl glycidyl ether were added under pressure using a buret. The reactor temperature rose to 120 ° C and was maintained at that temperature for 22 hours. Meanwhile, the pressure was changed from 7.7 × 10 ⁻⁵ Pa to 2.
It was significantly reduced to 6 × 10 ⁻⁵ Pa. The contents of the reactor were then poured into a glass flask containing 100 mg of 3-tert-butyl-4-hydroxy-5-methyl-phenylsulfate under an atmosphere of argon. 94.4 g of the copolymer was recovered after distilling the solvent and the yield of the copolymer was 94 without considering the copolymer not extracted from the reactor.
It was equivalent to%. DSC analysis of this copolymer shows a melting point T
f33 ° C and glass transition temperature Tg-59 ° C were shown. The number average molecular weight is determined by SEC and is about 110,00.
At 0, the multi-molecularity index was 2.2.

Example 4 A lithium battery operating at 60 ° C. and a composite TiS ₂ cathode were prepared using the material prepared according to Example 3.
A polymer electrolyte was prepared by dissolving the copolymer in 2% by weight of benzoyl peroxide and lithium bis (trifluorosulphonyl) imide (TFSI) dissolved in acetonitrile at an O / Li ratio of 30/1. Then the solution was poured into the form of a film having a thickness of 25 μm and the film was dried under vacuum at 90 ° C.
Similarly, some copolymers and TiS ₂ were mixed at a rate of close to 5% by weight to a composite electrode on nickel by a solvent method using Shawinigan black so that the capacity was 3 Cb / cm ^2. Was manufactured. 22 by sequentially pressing the film into the battery under vacuum at 85 ° C
Attach a lithium anode of μm, and then replace the battery with 6
Circulated at 0 ° C. It should be noted that the discharge rate (C /
6) and the charge rate (C / 12) is 1 without impairing the usage rate
The battery utilization rate is 8 during 50 cycles or more.
That is, it has been maintained at 5% or more. By this test, it was possible to confirm the electrochemical stability of the copolymer of the present invention having a high molecular weight.

Example 5 100 ml of THF, 0.1 g of potassium butanolate, 80 g of ethylene oxide (OE) and 9 g of allyl glycyl ether (AGE) were introduced into the reactor. This is O
This corresponds to an E / AGE ratio of 22. Reactor temperature is 12
The temperature rose to 0 ° C. and was maintained at that temperature for 6 hours, during which the pressure decreased from 7 × 10 ⁵ to 1.3 × 10 ⁵ . At the end of the reaction, the reaction mixture was deactivated by introducing methanol into the reactor, then some 3-tert-butyl-4-hydroxy-5-methyl-phenylsulfate was added. 87 g of the copolymer was recovered and then anio (An
io) 22, which corresponds to a substantially quantitative yield.
The characteristics of this copolymer are as follows: Mp = 12
10,000 g; Multimolecular index I = Mp / Mn = 1.9;
Tg = −62 ° C .; Tf = 35.6 ° C .; Crystallinity x = 0.3
7 2 in the copolymer Anio 22
The number of OE units between individual AGE units is
Assuming that there is a regular distribution of E units, ie 22 OE units between 2 AGE units were then evaluated by the method. This means that the melting temperature of the OE / AGE copolymer was found to be between n units OE and two AGE units, and was substantially the same as the melting temperature of polyethylene glycol (PEG), and its average molecular weight Mp was substantially the same. Array- (O
E) -n-, in other words assumed to be the same as Mp = nx44. Next, multiple melting temperatures of PEG with different molecular weights were determined and a curve Tf was generated as a function of Mp. FIG. 1 shows the change in melting temperature Tf, expressed in degrees Celsius as a function of average molecular weight and in grams as PEG (black triangle). The melting temperature of PEG is 8,
It increases rapidly with chain length reaching 65 ° C. for weights approaching 000 g. Furthermore, according to this curve, PEG
Has a melting temperature near 35 ° C. and PEG has an average molecular weight of about 1,000 g, which corresponds to about 22 OE units.

The molar ratios OE / AGE are 23 and 34, respectively.
And 45 (as the copolymer, Anio23 and An, respectively)
Three similar measurements were made from the copolymer obtained by using monomer amounts of io34, and Anio45). The melting temperature of each copolymer was determined, and FIG.
It is shown as a curve in (white square). Copolymer Anio _n
It was confirmed that the melting temperature of PEG was substantially the same as the melting temperature of PEG having a molecular weight substantially equal to n × 44. Thus, these tests show that the copolymer OE / AGE obtained by the polymerization process according to the invention
It was possible to confirm a regular distribution of the monomer units in.

Example 6 The copolymer Anio ₂₂ of Example 4 was crosslinked at 70 ° C. in the presence of 2% by weight of benzoyl peroxide with respect to the copolymer. The obtained crosslinked network has a melting temperature Tf = 28.
C, and a percentage of crystallinity x = 0.20. Many electrodes were produced in the form of films starting from the copolymer Anio ₂₂ . A solution of copolymer Anio ₂₂ , lithium trifluorosulfonylimide (TFSI) and benzoyl peroxide dissolved in acetonitrile was prepared while varying the TFSI content, and each solution was injected onto a support.
After evaporating the solvent, each film of the obtained copolymer was cross-linked by heating, maintained in a vacuum state for 7 days, and then stored in a glove box. The conductivity was determined at different temperatures between 20 and 84 ° C.

FIG. 2 shows the change in conductivity σ expressed in Ω ^-1 cm ^-1 as a function of temperature expressed in ° C for different electrolytes. The white circles represent the copolymer Anio, as is usually considered as the reference polymer with the best ionic conductivity.
₂₂ and an electrolyte consisting of a TFSI salt with an O / Li ratio = 14, the black circles being the copolymers Anio ₂₂ and O / Li.
Corresponding to an electrolyte composed of TFSI salt with a ratio of 16.7, the white Δ indicates the molecular weight of poly (oxyethylene) is 5 × 1.
0 ⁶ g / mol and TFSI salt content of O / Li
Rate = 8. The conductivity obtained from the electrolyte of the present invention is
Within the range investigated over a wide temperature range, it is higher than the remarkable conductivity obtained from the reference complex poly (oxyethylene).

DSC analysis confirmed the complete amorphous structure of the electrolyte. From Table 1 below, various glass transition temperatures Tg (° C.) were obtained for different salt concentrations, as indicated by the atomic ratio O / Li, and electrolytes prepared from the copolymers according to the invention. It was confirmed that the glass transition temperature of the spores increased slowly with the salt concentration.

[0070]

[Table 1]

Anio ₂₂ / Li having a reticulated structure of the electrolyte
The range of TFSI electrochemical stability was established by circulating coulometry on a potassium micro-electrode at 81 ° C. The obtained volt-amperog
rams) shows a lithium deposition layer in the form of a sharp peak at about OV vs lithium. A retun swee
p) indicates the reoxidation of alloys and intermetallics formed between platinum and lithium. Since no peaks result from the oxidation or reduction of the copolymer, the range of capabilities investigated, namely 0
It is clearly in the range of +3.9 VvsLi / Li +.

Thermogravimetric analysis is stable until the electrolyte reaches 240 ° C., at which temperature the dissolution of lithium is 1 even when the electrolyte is used in all solid state lithium batteries.
It already occurs at 80 ° C., indicating that it is of sufficient height.

Example 7 150 ml of THF, 0.12 g of potassium t-butanolate, 89 g of ethylene oxide (OE), 9.8 g of epoxyhexene and 8.4 g of the epoxide represented by the above formula (4) , R ′ is CH ₂ —O—CF ₂ —CF ₂ —
SO ₃ shows the -K group) was charged to the reactor. The reactor temperature rose to 110 ° C. and was maintained for 12 hours.
The reaction mixture is then inactivated by introducing methanol into the reactor, forming a precipitate in hexane,
It is possible to obtain 103 g of a polymer having an electrophoretic function. The yield is close to 96%.

The solution obtained by dissolving the precipitate in THF was subjected to CES analysis with two columns of CES 10 nm, and it was impossible to react. Above 4
It was not possible to detect the residue of the ionic monomer represented by.

Crosslinked membranes were prepared by adding 1% by weight of benzoyl peroxide (based on polymer) to a solution of the copolymer in a solvent and then heating at 80 ° C. for 2 hours. The conductivity of the obtained film was 10 ⁻⁵ S.C. at 37 ° C. cm ^-1
And 10 ^-4 S.C. at ^77.degree . cm ^-1 .

Analysis by DSC shows a melting point of 24 ° C.
The glass transition temperature was -55 ° C. A sample of the crosslinked film was dissolved in acetonitrile (CF ₃ SO ₂ ) ₂ N
The solution of Li was swollen three times to exchange the cation K ⁺ with the cation Li ⁺ . Then, transfer the membrane onto the filtration crucible,
The solution of acetonitrile was removed by filtration. The membrane was then washed 3 times with 50 ml of acetonitrile to remove slight traces of free salts and the membrane was carefully dried. The conductivity of this film is 10 ^-5 S.C. at 45 ° C. cm ^-1 and 10 ^-4 S.C. at 95 ° C. It was cm ^-1 . The melting point of this film is 2
It was 5 ° C, and its glass transition temperature was -57 ° C.

Example 8 An ion-conducting monopolar electrolyte was mixed with a double allyl bond (CH ₂ = CH).
It was prepared by co-crosslinking the copolymer Anio ₂₂ prepared according to Example 4 with an electrophoretic compound having —CH ₂ —O—CF ₂ —CF ₂ —SO ₃ Li). Crosslinking was carried out at 70 ° C. for 3 hours in the presence of 2% by weight benzoyl peroxide. The amount of electrophoretic compound added corresponds to an O / Li ratio of 15. Analysis of the solvent after washing the crosslinked film revealed that about 90% of the salt was mixed in the network structure. Therefore, O / L in the network structure
The i ratio is 17. DSA analysis shows a melting point peak at 19 ° C and a glass transition temperature of -58 ° C. Electrolyte 33 ° C
At 10 ^-5 S. cm ⁻¹ and 10 ⁻⁴ S.C. at 70 ° C. A conductivity of cm ^-1 is reached. The membrane was then swollen by incorporating 30% by weight of a mixture of propylene carbonate and ethylene carbonate in a 2/1 molar ratio. Then the conductivity was 5.10 ⁻⁵ S.C. at 20 ° C. cm ^-1 and 60 ° C
At 10 ^-3 S. It had reached cm ^-1 .

[Brief description of drawings]

The present invention is illustrative rather than limiting by the following figures.

FIG. 1 shows PEG, Anio ₂₃ , Anio ₃₄ and A.
It is a curve showing the change in melting point as a function of the average molecular weight of nio _45.

FIG. 2 shows conductivity σ as a function of temperature for different electrolytes.
Shows the change of.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Jean-Eve Saint-Cheer 38330 Saint-Ismier Simét Chartreuse 781 Le Chabou (72) Inventor Fanny Arois France 38100 Grenoble Abne Jeanne d'Arc 77

Claims (22)

[Claims] 1. Ethylene oxide, —O—CH ₂ —CHR—
A unit, where R is a substituent having a reactive function, which substituent is crosslinkable by a free radical process, and R may differ from one unit to another;
Optionally -O-CH ₂ -CHR ^'units (wherein, ^R'
Is a substituent containing a non-reactive function which is cross-linkable by free radical process, R ^'may be the units and other units that are different) a copolymer with a chain, including, co A copolymer characterized in that the polymer has an excellent heavy molecular weight index I = Mp / Mn and a statistical distribution of different monomer units. 2. The copolymer according to claim 1, which has a number average molecular weight (Mn) of 20,000 or more, more preferably 100,000 or more. 3. The copolymer according to claim 1, which has a heavy molecular weight ratio index of 2.2 or less. 4. The substituent R has the general formula (CH ₂ ═CH— (C
H ₂ ) q- (O-CH ₂ ) p (wherein 1 ≦ q ≦ 6 and p = 0 or 1), or the general formula (CH ₃ — (C
_{H 2) y-CH = CH-} (CH 2) x- (OCH 2) p
The copolymer according to claim 1, which is a group having (in the formula, 0 ≦ x + y ≦ 5 and p = 0 or 1). Wherein R ^'group is an alkyl group, preferably 1 to 1
Alkyl group having 6 carbon atoms ;-( CH ₂₎ n -O
_{- ((CH 2) m -O} ) p-CH 3 group (wherein, 0 ≦ n ≦
4, 1 ≦ m ≦ 4, and 0 ≦ p ≦ 20) and the like; an alkyl group (perfluoroalkyl sulfonate) ether group; a negative charge of bis (trifluoromethylsulfonyl) methylide carbanion-C (S
O ₂ CF ₃ ) ₂ M ″ (wherein M ″ is a metal cation, particularly a monovalent cation such as an alkali metal cation), and is selected from a group incorporating an electrophoretic function. The copolymer according to claim 1, which is characterized in that: 6. An ethylene oxide unit of at least 70 mol%.
%, About 2 to 30 mol% of —O—CH₂-CHR^'-Unit
And about 0.05 to about 10 mol% -O-CH. ₂-CHR
-Copolymerization according to claim 1, characterized in that it comprises units.
body. 7. A process for producing a copolymer from ethylene oxide and one or more substituted oxiranes (provided that at least one substituent R has a function capable of being crosslinked by a free radical process), ethylene oxide and The substituted oxirane is reacted in a neutral solvent in the presence of an initiator for ionic polymerization, the monomer and solvent used have a certain humidity and impurities of 100 ppm or less, and the reactor used for the polymerization reaction is A method for producing a copolymer characterized by being free from traces of impurities. 8. The method for producing the copolymer according to claim 7, wherein the polymerization initiator is selected from alkali metals used in a metal form, an alcoholate form, or a complex form. 9. The method for producing a copolymer according to claim 8, wherein the alkali metal is selected from cesium and potassium. 10. Machine capable of crosslinking by a free radical process.
A functional oxirane is represented by the following formula:[In the formula, R is a group containing an unsaturated carbon-carbon bond, or particularly
Formula CH₂= CH- (CH ₂) Q- (O-CH₂) P (expression
Where 1 ≦ q ≦ 6, and p = 0 or 1) or the formula CH₃
-(CH₂) Y-CH = CH- (CH₂) X − (OCH
₂) P (where 0 ≦ x + y ≦ 5 and p = 0 or 1)
Represented by
The method for producing a copolymer according to claim 7, characterized in that 11. The method for producing a copolymer according to claim 10, wherein the oxirane represented by the chemical formula 1 is allyl glycidyl ether or epoxy hexane. 12. Copolymerization of ethylene oxide with at least one oxirane capable of cross-linking by a free radical process is represented by the formula: Copolymerization according to claim 7, characterized in that it is carried out in the presence of at least one oxirane of the formula R'wherein R'is a substituent containing a non-reactive function which is crosslinkable by free radical processes. Manufacturing method of coalescence. 13. The R ′ group is an alkyl group, preferably 1 to
Alkyl group having 16 carbon atoms ;-( CH ₂₎ n -
_{O - ((CH 2) m} -O) p-CH 3 group (wherein, 0 ≦ n
≦ 4, 1 ≦ m ≦ 4, and 0 ≦ p ≦ 20); an alkyl group (perfluoroalkyl sulfonate) ether group; negative charge is bis (trifluoromethylsulfonyl) methylide carbanion-C
(SO ₂ CF ₃ ) ₂ M ″ (where M ″ is a metal cation,
13. The method for producing a copolymer according to claim 12, wherein the copolymer is selected from the group having an electrophoretic function generated by a monovalent cation such as an alkali metal cation. 14. The method for producing a copolymer according to claim 7, further comprising an addition step of inactivating the terminal function of the copolymer. 15. An ethylene oxide unit, —O—CH₂-C
HR-unit, where R is crosslinkable by a free radical process
R is a substituent containing an effective function, and R is a unit and another unit.
Can be different) and optionally -O-C
H₂-CHR ^'Unit (In the formula, R^'Is due to the free radical process
R is a substituent containing a non-reactive function which is crosslinkable by R
^'Can be different from one unit)
It is a copolymer and has an excellent heavy molecular weight index I = M.
p / Mn, statistical distribution of different monomer units and mean
At least 20,000, preferably at least
Copolymer having 100,000 as a polymer type solvent
An ion-conducting material characterized by containing. 16. The ion conductive material according to claim 15, further comprising a salt which can be easily decomposed. 17. The copolymer according to claim 1, wherein the copolymer is converted by grafting an ionic group to the reactive function of the substituent R of the —O—CH ₂ —CHR— unit.
5. The ion conductive material according to 5. 18. The copolymer is --O--CH ₂ --CHR '-.
The ion-conducting material according to claim 15, wherein the ion-conducting material contains units (wherein the R'group includes an ionic group). 19. The ion conductive material according to claim 15, which is swollen by a solvent. 20. Ethylene oxide, —O—CH ₂ —CHR
A unit (wherein R is a substituent containing a function capable of cross-linking by a free radical process, R may be different from one unit to another unit), and optionally —O—CH ₂
-CHR'- units (wherein, R 'is a substituent containing a non-crosslinkable functionality by free radical processes, ^R' is a unit with the other units may be different can) be a copolymer comprising And an excellent heavy molecular weight index I = Mp / Mn, a statistical distribution of different monomer units, and an ion conductive material containing a copolymer having a mean molecular weight of at least 20,000, preferably at least 100,000 as a polymer-type solvent. And / or at least one of the electrodes is a composite electrode comprising an ion-conducting material. 21. A rechargeable or non-rechargeable electrochemical generator comprising a negative electrode and a positive electrode separated by a solid polymer electrolyte comprising ethylene oxide, —O—CH ₂ —CHR. -Unit (in the formula, R
Is a substituent containing a function capable of being crosslinked by a free radical process, R may be different from one unit to another unit, and optionally a —O—CH ₂ —CHR ′ unit (in the formula, R'is a substituent containing a non-crosslinking function by a free radical process, R'is a copolymer containing one unit and another unit), and has an excellent heavy molecular weight index I = Mp / Mn, an electrolyte comprising an ion-conducting material comprising as copolymeric solvent a copolymer having a different monomer unit statistical distribution and an average molecular weight of at least 20,000, preferably at least 100,000;
And / or at least one of the electrodes is a composite electrode comprising an ion-conducting material, a rechargeable or non-rechargeable electrochemical generator. 22. Ethylene oxide, —O—CH ₂ —CHR
A unit (wherein R is a substituent containing a function capable of cross-linking by a free radical process, R may be different from one unit to another unit), and optionally —O—CH ₂
A -CHR 'unit, where R'is a substituent containing a non-crosslinking function by a free radical process and R'can be different from one unit to another unit, And an ion-conducting material containing as a polymer-type solvent a copolymer having an excellent heavy molecular weight ratio index I = Mp / Mn, a statistical distribution of different monomer units and an average molecular weight of at least 20,000, preferably at least 100,000. , For the production of electrochromic systems, light modulation systems, selective or reference membranes in membrane pickups.